The red-throated diver does indeed have a brick-red throat in its adult summer plumage. It has a white belly, silky dove-grey head and neck (with narrow black and white stripes on the back) and a piercing burgundy-coloured eye, a black tail and a spotted silvery grey/black back. The bill is thin, straight, black (in summer) and sharp, and often held at an up-tilted angle. It flies fast with the head and neck drooping.

Behaviour

The red-throated diver is a monogamous species that forms long term bonds with its mate. Both members of the pair help to build the nest, incubate the eggs, (generally two per clutch) and feed the young. Unlike other divers, it regularly uses very small freshwater lakes as breeding sites, where the nest is built close to the water’s edge and fish form the bulk of its diet.

The red-throated Diver is very vocal with a variety of calls. When in flight, when passing its ‘own’ lake, it gives a series of rapid yet rhythmic goose-like cackles – ‘kaa-kaa-kaa’ or ‘kak-kak-kak’. Its warning call, if disturbed by humans or predators, is a short croaking bark and it produces a low-pitched haunting moaning call used primarily as a contact call between mates and between parents and young. It is the only species of diver able to take off directly from land, where its movements are rather clumsy due to the feet being located so far back on its body.

Size

• Length: 53-69 cm
• Wingspan 91-120 cm
• Average weight: 2-2.3 kg
• Average lifespan: 9 years

Status

Classified in the UK as Green under the Birds of Conservation Concern 4: the Red List for Birds (2015); protected by The Wildlife and Countryside Act 1981.

Distribution

Scotland holds 100% of the British breeding population. Shetland is the UK stronghold (with over half of the Scottish breeding population) with other key populations on Orkney, the Outer Hebrides and the north Scottish mainland, as far south as the Mull of Kintyre, but in much reduced numbers.

When to see

January to December; nesting in the far north and Northern Isles in the summer and moving to the coast (largely to the east) in winter.

Facts

• The red-throated diver, also known in North America as the red-throated loon is the smallest, most slender and lightest of the world’s divers.
• As recently as the 1800s, the behaviour of the red-throated diver was used to forecast the weather; birds flying inland or giving short cries predicted good weather, while those flying out to sea or giving long, wailing cries predicted rain. In the Orkney and Shetland Islands the species is still known as the “rain goose” in reference to its apparent weather-predicting capabilities.